The "Mad Money" host hit rock bottom early in his career—at the time he was working as a journalist and making next to nothing. After a thief broke into his modest California apartment and stole absolutely everything, Cramer had nothing left and nowhere to go.

Cramer was living out of his car.

"I was living hand to mouth, and people would take me in now and then so I could get a shower, change, get a good night's sleep," he explained.

At that time in his life, it was a struggle for Cramer just to stay afloat; just to stay healthy. Yet all the while—he continued to put away a little money.

Cramer pared off a small percentage from each paycheck and sent that money to Fidelity for deposit in the Magellan Fund.

At that time in his life Cramer couldn't afford much—he had to make choices and set priorities. And though he had to go without many things, the virtues of saving money in a mutual fund and by proxy, owning stocks, was one the few things he just refused to forsake.

"I never quit saving," he said. "How poor was I, yet I still put away money."

Now Cramer understands that sometimes life is unkind and it's not always easy to save. But nonetheless, he advocates squirreling a little money away, no matter what.

The takeaway here, he said, is that you must try to save no matter what, through thick and thin. "If I could still save when I was living in my car, sick as a dog you can put away some money, too."